Despite a recent increase in the number of engineers graduating from U.S. universities, the nation will continue to face serious shortages of new technicians and engineers in the computer, electronics and metal-working fields during the 1980s, industry spokesmen said last week.

The gap jeopardizes the goals of the Reagan administration's defense program and the futures of many U.S. manufacturing companies threatened by foreign competition, said F. Karl Willenbrock, engineering professor at Southern Methodist University and spokesman for the American Electronics Association.

Willenbrock and other industry spokesmen testified at a Congressional Joint Economic Committee hearing conducted by Sen. Lloyd Bentsen (D-Tex.). Bentsen said Labor Department studies project a shortage of 2.5 million skilled workers during the 1980s, which "exists today hand in hand with 8 million men and women crowding into personnel offices looking for jobs, any jobs," said Bentsen.

U.S. companies must make engineering jobs more attractive if they expect to close the gap, said Sheldon Weinig, president of Materials Research Corp., speaking for the American Business Conference. His company maintains a no-layoff policy despite a current sales slump and fully reimburses employes who continue their education after work. "Real engineering doesn't pay in our society," Weinig said.

Based on the survey of nearly 700 electronics companies in the AEA, U.S. colleges and universities will produce only 35 percent of the electrical engineers and computer science engineers that will be needed over the next four years, for example.

"To meet just the needs of the electronics industry alone, the engineering schools would have to triple their output of electrical and computer science engineers each year for the next five years," Willenbrock said.

But shortages in engineering faculty and inadequate teaching facilities make it plain that no such dramatic increase will occur, he said.

A positive development is the recent increase in enrollment at engineering schools and the high quality of entering students, he said.

One reason is a "remarkable" increase in women students. In some engineering schools, 20 percent to 25 percent of the freshmen are women, while only one percent of the nation's engineers are women, he added. There is also a growing number of minority students taking engineering.

"The shortage of engineering talent in the United States does not stem primarily from a lack of students but rather with the shortage of engineering resources to educate them," he said.